CN-117816955-B - Z-type heterojunction composite material and preparation method and application thereof

Abstract

The invention belongs to the technical fields of photoelectric active materials and photoelectric sensing analysis, and particularly relates to a Z-type heterojunction composite material and a preparation method and application thereof. The composite material is annealed by taking Ti-MOF as a precursor to obtain a carboxyl functionalized p-type 2DTiO 2 @C nano cake, auNPs are formed on the surface of the 2DTiO 2 @C nano cake in situ by chemical reduction to obtain a p-type 2DTiO 2 @C/Au nano cake, an amino modified p-type 3D peony-shaped BiOI is added into the p-type 2DTiO 2 @C/Au nano cake, and the 2DTiO 2 @C/Au/3DBiOIZ heterojunction composite material is obtained through electrostatic interaction. The Z-type heterojunction composite material is designed and prepared by adopting the metal-organic framework template auxiliary calcination method, chemical reduction and electrostatic interaction, so that the photoelectric activity is improved, and the rapid, high-sensitivity, accurate and reliable hexavalent chromium ion detection is realized.

Inventors

• Meng Leixia
• ZHANG YU
• WANG JINLONG
• ZHOU BINGXIN
• ZHANG GUANGHUI
• DING SHUANGSHUANG
• LI HUIJUN
• XU ZHOUQING

Assignees

• 河南理工大学

Dates

Publication Date

20260505

Application Date

20230613

Claims (10)

1. 1. A Z-type heterojunction composite material is characterized in that Ti-MOF is used as a precursor, carboxyl-functionalized p-type 2DTiO 2 @C nano-cakes are obtained by annealing at 300-400 ℃, HAuCl 4 is subjected to chemical reduction to form AuNPs on the surface of the 2DTiO 2 @C nano-cakes in situ, p-type 2DTiO 2 @C/Au nano-cakes are obtained, and then amino-modified p-type 3D peony-shaped BiOI is added into the p-type 2DTiO 2 @C/Au nano-cakes, and the 2DTiO 2 @C/Au/3 DBiOIZ-type heterojunction composite material is obtained through electrostatic interaction.
2. 2. The method of preparing a Z-type heterojunction composite material as claimed in claim 1, comprising the steps of: S1, preparing a 2DTiO 2 @C nanometer cake, namely dissolving 1, 4-phthalic acid into a mixed solvent to form a mixed solution, adding tetrabutyl titanate, uniformly mixing, performing solvothermal reaction, centrifuging, washing and drying after the reaction is finished to obtain a Ti-MOF precursor, and annealing the Ti-MOF precursor at 300-400 ℃ to obtain a carboxyl functionalized p-type 2DTiO 2 @C nanometer cake; S2, preparing a 2DTiO 2 @C/Au nano cake, namely dispersing the p-type 2DTiO 2 @C nano cake in water, adding HAuCl 4 solution to form suspension, then adding NaBH 4 solution, carrying out reduction reaction at room temperature, centrifuging after the reaction is finished, washing and drying to obtain a carboxyl functionalized 2DTiO 2 @C/Au nano cake; S3, adding the 3D peony-shaped BiOI suspension modified by the amino into the 2DTiO 2 @C/Au nano cake suspension functionalized by the carboxyl, stirring at room temperature for reaction, centrifuging, washing and drying to obtain the Z-shaped heterojunction composite material.
3. 3. The preparation method of the Z-type heterojunction composite material according to claim 2 is characterized in that in S1, the mass volume ratio of the 1, 4-phthalic acid to the mixed solvent to the tetrabutyl titanate is 2.5-4.5 g:49-70 mL:2.5-4.0 mL, and the mixed solvent is formed by mixing N, N-dimethylformamide and anhydrous methanol according to the volume ratio of 44-60 mL:5-10 mL.
4. 4. The method for preparing the Z-type heterojunction composite material according to claim 2, wherein in S1, the solvothermal reaction is carried out at a temperature of 100-200 ℃ for 24-54 h, drying is carried out at 60 ℃ overnight, annealing is carried out for 4-8 h, and the temperature rising rate is 2-15 ℃ per minute.
5. 5. The preparation method of the Z-type heterojunction composite material according to claim 2, wherein in S2, the mass volume ratio of the p-type 2DTiO 2 @C nano cake, water, HAuCl 4 solution and NaBH 4 solution is 200-600 mg:200-400 mL:2-5 mL:15-30 mL, the concentration of the HAuCl 4 solution is 5-20wt%, the concentration of the NaBH 4 solution is 0.05-1.2M, the room temperature reduction reaction time is 15min, and the drying is carried out under vacuum at 60 ℃ until the weight is constant.
6. 6. The method for preparing a Z-type heterojunction composite material according to claim 2, wherein in S3, the method for preparing the amino-modified 3D peony-like bisi comprises the following steps: Dissolving Bi (NO 3 ) 3 ·5H 2 O in ethanol to form a solution A, dissolving KI in water to form a solution B, mixing the two solutions, stirring for 1h, performing solvothermal reaction, centrifuging, washing and drying to obtain 3D peony-shaped p-type BiOI, dispersing the 3D peony-shaped p-type BiOI in the mixed solution, performing ultrasonic dispersion, adding aminopropyl triethoxysilane, stirring for 12h, reacting at 75 ℃, centrifuging, washing and drying after the reaction is finished to obtain the amino-modified 3D peony-shaped BiOI.
7. 7. The method of claim 6, wherein the Bi (molar volume ratio of NO 3 ) 3 ·5H 2 O to ethanol is 1.5mmol:30ml, the molar volume ratio of KI to water is 1.5mmol:30ml, the volume ratio of solution a to solution B is 1:1, the solvothermal reaction temperature is 180 ℃, and the time is 12h.
8. 8. The method for preparing the Z-type heterojunction composite material according to claim 6, wherein the mass volume ratio of the 3D peony-shaped p-type BiOI to the mixed solution to the aminopropyl triethoxysilane is 100mg to 100mL to 1mL, the mixed solution is formed by mixing ethanol and water in a volume ratio of 19 to 1, the ultrasonic time is 30min, the reaction time is 1h, and the drying is performed at 60 ℃ overnight.
9. 9. The preparation method of the Z-shaped heterojunction composite material according to claim 2, wherein in S3, the volume ratio of the amino-modified 3D peony-shaped BiOI suspension to the carboxyl-functionalized 2DTiO 2 @C/Au nano-cake suspension is 9:1, the amino-modified 3D peony-shaped BiOI suspension is an aqueous solution with the concentration of 1mg/mL, the carboxyl-functionalized 2DTiO 2 @C/Au nano-cake suspension is an aqueous solution with the concentration of 1mg/mL, the room temperature reaction time is 6 hours, and the carboxyl-functionalized 2DTiO 2 @C/Au nano-cake suspension is dried to constant weight under the condition of 60 ℃.
10. 10. Use of the Z-type heterojunction composite material according to claim 1 in a hexavalent chromium ion photoelectric sensing analysis, characterized in that the 2DTiO 2 @ C/Au/3DBiOIZ type heterojunction composite material is constructed as a photoelectrochemical sensor, and the photoelectrochemical response of the photoelectrochemical sensor to hexavalent chromium ions is utilized to realize the detection of the concentration of hexavalent chromium ions.

Description

Z-type heterojunction composite material and preparation method and application thereof Technical Field The invention belongs to the technical fields of photoelectric active materials and photoelectric sensing analysis, and particularly relates to a Z-type heterojunction composite material and a preparation method and application thereof. Background Heavy metal ion pollution, one of the most serious problems of natural environment and human health, has attracted great attention. Hexavalent chromium (Cr (VI)) ions, according to the class I classification of the international cancer research institute (International Agency for Research on Cancer), can cause genetic defects, genotoxic tumors, allergies and asthma, and compromise the environment by accumulating in the surrounding environment and the food chain, and thus attracts attention of researchers. Therefore, the detection of Cr (VI) ions is of great importance for environmental protection, human health and food safety. Today, various methods have been developed to detect Cr (VI) ions, including electrochemical analysis, fluorescence spectroscopy, ion chromatography, atomic absorption spectroscopy, high performance liquid chromatography-inductively coupled plasma mass spectrometry, colorimetric detection, and the like. Although the above detection method has considerable sensitivity and accuracy, there are drawbacks of complicated and laborious processes, expensive equipment, and professional operators, etc., and Photoelectrochemical (PEC) sensors are focused on by researchers with advantages of low cost, fast response, easy operation, high sensitivity, etc. Since the detection performance of PEC sensors depends mainly on the electro-optically active material, the selection and design of suitable semiconductor materials is important for developing high performance PEC sensors. Currently, researchers have developed a variety of optoelectronic materials to improve the sensitivity of PEC sensors. However, the single photoelectric material and the conventional heterojunction generally have the problems of small light absorption range and low electron-hole separation efficiency. Therefore, there is a necessary trend to search for novel photoelectric materials with high photoelectric conversion efficiency. The photoelectric activity of the material can be improved through morphology regulation and heterojunction construction. With the development of nanostructure engineering in terms of morphology regulation, zero-dimensional (0D) quantum dots, one-dimensional (1D) nanorods, two-dimensional (2D) nanoflower, and three-dimensional (3D) flower-like nanostructures have been developed as excellent photoelectric materials. Heterojunction construction has proven to be an effective method of inhibiting photo-generated electron-hole pair recombination. However, conventional heterojunctions such as type II heterojunctions, schottky junctions, homojunctions, etc. have low electron-hole separation efficiency and insufficient photoelectric conversion efficiency, so how to construct a Z-type heterojunction composite material with excellent photoelectric properties to form a Photoelectrochemical (PEC) sensor so as to realize the analysis and detection of Cr (VI) ions is still a challenge for environmental monitoring and human health assurance. Disclosure of Invention In order to solve the problems, the invention provides a Z-type heterojunction composite material, a preparation method and application thereof, wherein the Z-type heterojunction composite material is prepared by adopting a metal-organic framework (MOF) template auxiliary calcination method, chemical reduction and electrostatic interaction for the first time, so that the photoelectric activity is improved, and the rapid, low-cost, high-sensitivity and accurate and reliable-result Cr (VI) ion detection is realized based on the Z-type heterojunction composite material. The invention solves the technical problems through the following technical proposal. The first object of the application is to provide a Z-type heterojunction composite material, which takes Ti-MOF as a precursor, anneals at 300-400 ℃ to obtain carboxyl-functionalized p-type 2D TiO 2 @C nano-cakes, forms AuNPs on the surface of the 2D TiO 2 @C nano-cakes in situ by HAuCl 4 through chemical reduction to obtain p-type 2D TiO 2 @C/Au nano-cakes, and then adds amino-modified p-type 3D peony flower-shaped BiOI into the p-type 2D TiO 2 @C/Au nano-cakes to obtain the 2D TiO 2 @C/Au/3D BiOI Z-type heterojunction composite material through electrostatic interaction. The second object of the present application is to provide a method for preparing the above-mentioned Z-type heterojunction composite material, comprising the following steps: S1, preparing a 2D TiO 2 @C nano cake, namely dissolving 1, 4-phthalic acid into a mixed solvent to form a mixed solution, adding tetrabutyl titanate, uniformly mixing, performing solvothermal reaction, centrifuging, washin